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    // Registers value copy loop
    xor        A                        // 5    Register number (0 to 13)
    ld        C, #PSG_PORT_REGS        // 8    Port number
    ld        HL, #_g_PSG_Registers    // 11    Data to copy to PSG registers
RegCopyLoop:
    out        (C), A                    // 14    port_reg <- reg_num
    inc        C                        // 5
    outi                            // 18    port_data <- data[i++]
    dec        C                        // 5
    inc        A                        // 5
    cp        #13                        // 8
    jr        NZ, RegCopyLoop            // 13/8
    out        (C), A                    // 14
    ld        A, (HL)                    // 8
    and        A                        // 5
    ret        M                        // 12
    inc        C                        // 5
    out        (C), A                    // 14
 

// Registers value copy loop
    ld        HL, #_g_PSG_Registers    // 11    Data to copy to PSG registers
    ld        C, #PSG_PORT_DATA        // 8    Setup outi register
    xor        A                        // 5    Initialize register number
    // R#0-12
    .rept 13
        out        (PSG_PORT_REGS), A    // 12    port_reg <- reg_num
        outi                        // 18    port_data <- data[i++]
        inc        A                    // 5
    .endm
    // R#13
    out        (PSG_PORT_REGS), A        // 12    port_reg <- reg_num
    ld        A, (HL)                    // 8
    and        A                        // 5
    ret        M                        // 12    don't copy R#13 if value is negative
    out        (PSG_PORT_DATA), A        // 12    port_data <- data[i]
 

 
u8 g_PSG_Registers[14]; // Mon buffer de registres du PSG
#define PSG_PORT_REGS    0xA0   ///< Used to select a specific register by writing its number (0 to 15)
#define PSG_PORT_DATA    0xA1   ///< Used to write to any register once it has been selected by the Address Port.    
#define PSG_PORT_STAT    0xA2   ///< Used to read any register once it has been selected by the Address Port.
 

#ifdef __SDCC_OPTIMIZE_SIZE
    // version original
#else
    // ma version
#endif